Method of making a metal injection molded ammunition cartridge

ABSTRACT

The present invention provides a method of making a metal injection molded ammunition cartridge comprising the steps of: providing an ammunition cartridge mold comprising a bottom portion having a primer recess extending into the bottom portion adapted to receive a primer, a flash hole positioned in the primer recess through the bottom surface; side walls extending from the bottom portion to a nose end aperture, wherein a propellant chamber is formed between the nose end aperture and the bottom surface; injecting a metal composition into the ammunition cartridge mold to form a metal injection molded ammunition cartridge; and removing the metal injection molded ammunition cartridge from the ammunition cartridge mold.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/863,800 filed Sep. 24, 2015 now U.S. Pat. No. 10,041,770, which is acontinuation of U.S. patent application Ser. No. 14/011,202 filed Aug.27, 2013, now U.S. Pat. No. 9,546,849 issued Jan. 17, 2017, which is acontinuation of U.S. patent application Ser. No. 13/292,843 filed Nov.9, 2011, now U.S. Pat. No. 8,561,543 issued Oct. 22, 2013, and claimsthe benefit of U.S. Patent Application No. 61/456,664 filed Nov. 10,2010, all of which are incorporated herein by reference.

TECHNICAL FIELD OF THE INVENTION

The present invention relates in general to the field of ammunition,specifically to compositions of matter and methods of making metalcartridge cases by metal injection molding.

STATEMENT OF FEDERALLY FUNDED RESEARCH

None.

INCORPORATION-BY-REFERENCE OF MATERIALS FILED ON COMPACT DISC

None.

BACKGROUND OF THE INVENTION

Without limiting the scope of the invention, its background is describedin connection with projectiles made by injection molding for use inammunition. Conventional ammunition casings for rifles and machine guns,as well as larger caliber weapons, are made from brass or lead that aremachined.

Shortcomings of the known methods of producing ammunition cartridgesinclude the limitation of materials that can be used and the lengthytime for manufacturing.

BRIEF SUMMARY OF THE INVENTION

The present invention provides a method of making a metal injectionmolded ammunition cartridge comprising the steps of: providing anammunition cartridge mold comprising a bottom portion having a primerrecess extending into the bottom portion adapted to receive a primer, aflash hole positioned in the primer recess through the bottom surface;side walls extending from the bottom portion to a nose end aperture,wherein a propellant chamber is formed between the nose end aperture andthe bottom surface; injecting a metal composition into the ammunitioncartridge mold to form a metal injection molded ammunition cartridge,wherein the metal composition comprises stainless steel, brass, ceramicalloys, copper/cobalt/nickel/custom alloys, tungsten, tungsten carbide,carballoy, ferro-tungsten, titanium, copper, cobalt, nickel, uranium,depleted uranium, alumina oxide, zirconia and aluminum; and removing themetal injection molded ammunition cartridge from the ammunitioncartridge mold.

The metal injection molded ammunition cartridge method furthercomprising the step of forming a shoulder in the metal injection moldedammunition cartridge. The metal injection molded ammunition cartridgemethod further comprising the step of forming a neck between theshoulder and the nose end aperture to form a projectile aperture. Themetal composition comprises: a) 2-16% Ni; 10-20% Cr; 0-5% Mo; 0-0.6% C;0-6.0% Cu; 0-0.5% Nb+Ta; 0-4.0% Mn; 0-2.0% Si and the balance Fe; b)2-6% Ni; 13.5-19.5% Cr; 0-0.10% C; 1-7.0% Cu; 0.05-0.65% Nb+Ta; 0-3.0%Mn; 0-3.0% Si and the balance Fe; c) 3-5% Ni; 15.5-17.5% Cr; 0-0.07% C;3-5.0% Cu; 0.15-0.45% Nb+Ta; 0-1.0% Mn; 0-1.0% Si and the balance Fe; d)10-14% Ni; 16-18% Cr; 2-3% Mo; 0-0.03% C; 0-2% Mn; 0-1% Si and thebalance Fe; e) 12-14% Cr; 0.15-0.4% C; 0-1% Mn; 0-1% Si and the balanceFe; f) 16-18% Cr; 0-0.05% C; 0-1% Mn; 0-1% Si and the balance Fe; g)3-12% aluminum, 2-8% vanadium, 0.1-0.75% iron, 0.1-0.5% oxygen, and theremainder titanium; or h) about 6% aluminum, about 4% vanadium, about0.25% iron, about 0.2% oxygen, and the remainder titanium. In oneembodiment the metal composition comprises 102, 174, 201, 202, 300, 302,303, 304, 308, 309, 316, 316L, 316Ti, 321, 405, 408, 409, 410, 415, 416,416R, 420, 430, 439, 440, 446 or 601-665 grade stainless steel. In oneembodiment the metal composition comprises 2-16% Ni; 10-20% Cr; 0-5% Mo;0-0.6% C; 0-6.0% Cu; 0-0.5% Nb+Ta; 0-4.0% Mn; 0-2.0% Si and the balanceFe; 2-6% Ni; 13.5-19.5% Cr; 0-0.10% C; 1-7.0% Cu; 0.05-0.65% Nb+Ta;0-3.0% Mn; 0-3.0% Si and the balance Fe; 3-5% Ni; 15.5-17.5% Cr; 0-0.07%C; 3-5.0% Cu; 0.15-0.45% Nb+Ta; 0-1.0% Mn; 0-1.0% Si and the balance Fe;10-14% Ni; 16-18% Cr; 2-3% Mo; 0-0.03% C; 0-2% Mn; 0-1% Si and thebalance Fe; 12-14% Cr; 0.15-0.4% C; 0-1% Mn; 0-1% Si and the balance Fe;16-18% Cr; 0-0.05% C; 0-1% Mn; 0-1% Si and the balance Fe; 3-12%aluminum, 2-8% vanadium, 0.1-0.75% iron, 0.1-0.5% oxygen, and theremainder titanium; or 6% aluminum, about 4% vanadium, about 0.25% iron,about 0.2% oxygen, and the remainder titanium. In one embodiment themetal composition comprises brass or a brass alloy.

The present invention provides a method of making a metal injectionmolded ammunition cartridge comprising the steps of: providing anammunition cartridge mold comprising a bottom portion having a primerrecess extending into the bottom portion adapted to receive a primer, aflash hole positioned in the primer recess through the bottom surface;side walls extending from the bottom portion to a nose end aperture,wherein a propellant chamber is formed between the nose end aperture andthe bottom surface;

injecting a metal composition into the ammunition cartridge mold to forma metal injection molded ammunition cartridge, wherein the metalcomposition comprises 2-16% Ni; 10-20% Cr; 0-5% Mo; 0-0.6% C; 0-6.0% Cu;0-0.5% Nb+Ta; 0-4.0% Mn; 0-2.0% Si and the balance Fe; 2-6% Ni;13.5-19.5% Cr; 0-0.10% C; 1-7.0% Cu; 0.05-0.65% Nb+Ta; 0-3.0% Mn; 0-3.0%Si and the balance Fe; 3-5% Ni; 15.5-17.5% Cr; 0-0.07% C; 3-5.0% Cu;0.15-0.45% Nb+Ta; 0-1.0% Mn; 0-1.0% Si and the balance Fe; 10-14% Ni;16-18% Cr; 2-3% Mo; 0-0.03% C; 0-2% Mn; 0-1% Si and the balance Fe;12-14% Cr; 0.15-0.4% C; 0-1% Mn; 0-1% Si and the balance Fe; 16-18% Cr;0-0.05% C; 0-1% Mn; 0-1% Si and the balance Fe; 3-12% aluminum, 2-8%vanadium, 0.1-0.75% iron, 0.1-0.5% oxygen, and the remainder titanium;or 6% aluminum, about 4% vanadium, about 0.25% iron, about 0.2% oxygen,and the remainder titanium; and removing the metal injection moldedammunition cartridge from the ammunition cartridge mold.

The present invention provides a method of making a metal injectionmolded ammunition cartridge comprising the steps of: providing anammunition cartridge mold comprising a bottom portion having a primerrecess extending into the bottom portion adapted to receive a primer, aflash hole positioned in the primer recess through the bottom surface;side walls extending from the bottom portion to a nose end aperture,wherein a propellant chamber is formed between the nose end aperture andthe bottom surface; injecting a metal composition into the ammunitioncartridge mold to form a metal injection molded ammunition cartridge,wherein the metal composition comprises a) 2-16% Ni; 10-20% Cr; 0-5% Mo;0-0.6% C; 0-6.0% Cu; 0-0.5% Nb+Ta; 0-4.0% Mn; 0-2.0% Si and the balanceFe; b) 2-6% Ni; 13.5-19.5% Cr; 0-0.10% C; 1-7.0% Cu; 0.05-0.65% Nb+Ta;0-3.0% Mn; 0-3.0% Si and the balance Fe; c) 3-5% Ni; 15.5-17.5% Cr;0-0.07% C; 3-5.0% Cu; 0.15-0.45% Nb+Ta; 0-1.0% Mn; 0-1.0% Si and thebalance Fe; d) 10-14% Ni; 16-18% Cr; 2-3% Mo; 0-0.03% C; 0-2% Mn; 0-1%Si and the balance Fe; e) 12-14% Cr; 0.15-0.4% C; 0-1% Mn; 0-1% Si andthe balance Fe; f) 16-18% Cr; 0-0.05% C; 0-1% Mn; 0-1% Si and thebalance Fe; g) 3-12% aluminum, 2-8% vanadium, 0.1-0.75% iron, 0.1-0.5%oxygen, and the remainder titanium; or h) about 6% aluminum, about 4%vanadium, about 0.25% iron, about 0.2% oxygen, and the remaindertitanium; and removing the metal injection molded ammunition cartridgefrom the ammunition cartridge mold.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

For a more complete understanding of the features and advantages of thepresent invention, reference is now made to the detailed description ofthe invention along with the accompanying figures and in which:

FIG. 1a depicts an exploded view of the polymeric cartridge casing.

FIG. 1b depicts an exploded view of the polymeric cartridge casing.

FIG. 2 is an image of a flat tip boattail projectile.

FIG. 3 is an image of a full metal jacket, expanding full metal jacket,spritzer, jacketed spritzer, armor piercing, armor piercing incendiaryor a similar projectile having a pointed nose and a boattail configuredend.

FIG. 4 is an image of a flat tip projectile with a flat base configuredend.

FIG. 5 is an image of a full metal jacket, expanding full metal jacket,spritzer, jacketed spritzer, armor piercing, armor piercing incendiaryor a similar projectile having a pointed nose and a flat base configuredend.

FIG. 6 is an image of a boattail configured end projectile without acannelure.

FIG. 7 is an image of a flat base configured end projectile without acannelure.

FIG. 8 is an image of a boattail configured end projectile with roundednose.

FIG. 9 is an image of a flat base projectile with a rounded nose.

FIG. 10 is an image of a flat base configured end projectile havingmultiple cannelures.

FIG. 11 is an image of a boattail configured end projectile havingmultiple cannelures.

FIG. 12 is a cut away image of a jacketed spritzer projectile.

FIG. 13 is a cut away image of a jacketed projectile.

FIG. 14 is a cut away image of a jacketed projectile.

FIG. 15 is a cut away image of a jacketed projectile.

FIG. 16 is a cut away image of a jacketed projectile.

FIG. 17 is a cut away image of a jacketed projectile.

FIG. 18 is a cut away image of a jacketed projectile.

FIGS. 19a-19s are images of a cut away image of different projectiletypes.

FIGS. 20a-20v are images of different embodiments of the projectiles ofthe present invention.

FIG. 21 depicts a side, cross-sectional view of a portion of thepolymeric cartridge case according to one embodiment of the presentinvention.

DETAILED DESCRIPTION OF THE INVENTION

While the making and using of various embodiments of the presentinvention are discussed in detail below, it should be appreciated thatthe present invention provides many applicable inventive concepts thatcan be embodied in a wide variety of specific contexts. The specificembodiments discussed herein are merely illustrative of specific ways tomake and use the invention and do not delimit the scope of theinvention.

As used herein the term “shell,” “bullet” and “projectile” are usedinterchangeably and denote a projectile that is positioned in anammunition cartridge until it is expelled from a gun, rifle, or the likeand propelled by detonation of a powdered chemical propellant or otherpropellant that may be non-powdered, solid, gaseous or gelatin. Andincludes payload-carrying projectiles contains shot, an explosive orother filling, though modern usage sometimes includes large solidprojectiles properly termed shot (AP, APCR, APCNR, APDS, APFSDS andproof shot).

As used herein AP denotes Armor Piercing (has a steel or other hardmetal core Military); API denotes Armor Piercing Incendiary (Military);APT denotes Armor Piercing Tracer (Military); APTI denotes ArmorPiercing Tracer Incendiary (Military); BBWC denotes Bevel Base WadCutter; BT denotes Boat Tail; BTBT denotes Ballistic Tip Boat Tail; BTHPdenotes Boat Tail Hollow Point; BTSP denotes Boat Tail Soft Point; FEBdenotes Fully Encased Bullet; FMC denotes Full Metal Case; FMJ denotesFull Metal Jacket; FMJBT denotes Full Metal Jacket Boat Tail; FMJFNdenotes Full Metal Jacket Flat Nose; FMJFP denotes Full Metal JacketFlat Point; FMJRN denotes Full Metal Jacket Round Nose; FMJRP denotesFull Metal Jacket Round Point; FMJSWC denotes Full Metal Jacket Semi-WadCutter; FMJTC denotes Full Metal Jacket Truncated Cone; FN denotes FlatNose; FNEB denotes Flat Nose Enclosed Base; FNSP denotes Flat Nose SoftPoint; FP denotes Flat Point; HE denotes High Energy or high explosive;HP denotes Hollow Point; HPBT denotes Hollow Point Boat Tail; J denotesJacketed; JFP denotes Jacketed Flat Point; JHP denotes Jacketed HollowPoint; JHPBT denotes Jacketed Hollow Point Boat Tail; JSP denotesJacketed Soft Point; JSPF denotes Jacketed Soft Point Flat; L denotesLead; LFN denotes Lead Flat Nose; LFP denotes Lead Flat Point; LHPdenotes Lead Hollow Point; LRN denotes Lead Round Nose; LSWC denotesLead Semi-Wad Cutter; LSWC-GC denotes Lead Semi-Wad Cutter, Gas Checked;LTC denotes Lead Truncated Cone; LWC denotes Lead Wad Cutter; RN denotesRound Nose; RNFP denotes Round Nose Flat Point; RNL denotes Round NosedLead; RNSP denotes Round Nose Soft Point; SJHP denotes Semi JacketedHollow Point, Soft Jacket Hollow Point; SJSP denotes Soft Jacket SoftPoint; SLAP denotes Saboted Light Armor Penetrating; SPTZ denotesSpitzer; Sub denotes Subsonic; SWC denotes Semi Wad Cutter; TC denotesTruncated Cone; TCMJ denotes Truncated Cone Metal Jacket; WC denotes WadCutter; AP denotes Armor piercing; API denotes Armor piercingincendiary; APIT denotes Armor piercing incendiary tracer; APT denotesArmor piercing tracer; CA denotes Copper Alloy; CAL denotes Caliber;GMCS denotes Gilding metal clad steel; HEAT denotes High-explosiveanti-tank; HEI denotes High explosive incendiary; HEIT denotes Highexplosive, incendiary, tracer; RAP denotes Rocket Assisted Projectile;and TPT Target practice, tracer.

Reliable projectile manufacture requires uniformity from one projectileto the next in order to obtain consistent ballistic performance. Inaddition to projectile shape, other considerations, proper projectileseating and bullet-to-casing fit is required. In this manner, a desiredpressure develops within the casing during firing prior to bullet andcasing separation. Historically, projectile employ a cannelure, which isa slight annular depression formed in a surface of the projectile at alocation determined to be the optimal seating depth for the bullet. Inthis manner, a visual inspection of a cartridge could determine whetheror not the bullet is seated at the proper depth. Once the bullet isinserted into the casing to the proper depth, one of two standardprocedures is incorporated to lock the bullet in its proper location.One method is the crimping of the entire end of the casing into thecannelure. A second method does not crimp the casing end; rather thebullet is pressure fitted into the casing, another method employsadhesive bonding to join the bullet to the casing.

FIG. 1a depicts an exploded view of the polymeric cartridge casinghaving an over-molded primer insert. A cartridge casing 10 suitable foruse with rifles is shown manufactured with a casing 12 showing apropellant chamber 14 with a projectile 56 inserted into the forward endopening 16. The cartridge casing 12 has a substantially cylindricalopen-ended bullet-end component 18 extending from the forward endopening 16 rearward to the opposite end 20. The forward end ofbullet-end component 18 has a shoulder 24 forming a chamber neck 26. Thebullet-end component 18 may be formed with coupling end 22 formed onsubstantially cylindrical opposite end 20 or formed as a separatecomponent. These and other suitable methods for securing individualpieces of a two-piece or multi-piece cartridge casing are useful in thepractice of the present invention. Coupling end 22 is shown as a maleelement, but may also be configured as a female element in alternateembodiments of the invention. In some embodiments the forward end ofbullet-end component 18 includes the forward end opening 16 without ashoulder 24 forming chamber neck 26. The bullet-end component typicallyhas a wall thickness between about 0.003 and about 0.200 inches and morepreferably between about 0.005 and more preferably between about 0.150inches about 0.010 and about 0.050 inches. The middle body component 28is substantially cylindrical and connects the forward end of bullet-endcomponent 18 to the substantially cylindrical opposite end 20 and formsthe propellant chamber 14. The substantially cylindrical opposite end 20includes a substantially cylindrical insert 32 that partially seals thepropellant chamber 14. In a two piece design as shown in FIG. 1a thesubstantially cylindrical insert 32 is molded into the middle bodycomponent 28. The substantially cylindrical insert 32 includes a bottomsurface (not shown) located in the propellant chamber 14 that isopposite a top surface (not shown). The substantially cylindrical insert32 includes a primer recess (not shown) positioned in the top surface(not shown) extending toward the bottom surface (not shown) with aprimer flash hole aperture (not shown) is located in the primer recess(not shown) and extends through the bottom surface (not shown) into thepropellant chamber 14 to combust the propellant in the propellantchamber 14. A primer (not shown) is located in the primer recess (notshown) and extends through the bottom surface (not shown) into thepropellant chamber 14. In some embodiments the coupling end 22 extendsthe polymer through the primer flash hole aperture (not shown) to formthe primer flash hole (not shown) while retaining a passage from the topsurface (not shown) through the bottom surface (not shown) and into thepropellant chamber 14 to provide support and protection about the primerflash hole aperture (not shown). In other embodiments the coupling end22 extends the polymer up to but not into the primer flash hole aperture(not shown) to form the primer flash hole (not shown) while retaining apassage from the top surface (not shown) through the bottom surface (notshown) and into the propellant chamber 14. The bullet-end 18, middlebody 28 and bottom surface (not shown) define the interior of propellantchamber 14 in which the powder charge (not shown) is contained. Theinterior volume of propellant chamber 14 may be varied to provide thevolume necessary for complete filling of the propellant chamber 14 bythe propellant chosen so that a simplified volumetric measure ofpropellant can be utilized when loading the cartridge. The bullet-endand bullet components can then be welded or bonded together usingsolvent, adhesive, sintering, brazing, soldering, spin-welding,vibration-welding, ultrasonic-welding or laser-welding techniques. Thewelding or bonding increases the joint strength so the casing can beextracted from the hot gun casing after firing at the cook-offtemperature. An optional first and second annular grooves (cannelures)may be provided in the bullet-end in the interlock surface of the malecoupling element to provide a snap-fit between the two components. Thecannelures formed in a surface of the bullet at a location determined tobe the optimal seating depth for the bullet. Once the bullet is insertedinto the casing to the proper depth to lock the bullet in its properlocation. One method is the crimping of the entire end of the casinginto the cannelures. The bullet-end and middle body components can thenbe welded or bonded together using solvent, adhesive, sintering,brazing, soldering, spin-welding, vibration-welding, ultrasonic-weldingor laser-welding techniques. The welding or bonding increases the jointstrength so the casing can be extracted from the hot gun casing afterfiring at the cook-off temperature.

FIG. 1b depicts an exploded view of a three piece polymeric cartridgecasing. A cartridge casing 10 suitable for use with rifles is shownmanufactured with a casing 12 showing a propellant chamber 14 with aprojectile 56 inserted into the forward end opening 16. The cartridgecasing 12 has a substantially cylindrical open-ended bullet-endcomponent 18 extending from the forward end opening 16 rearward to theopposite end 20. The forward end of bullet-end component 18 has ashoulder 24 forming a chamber neck 26. The bullet-end component 18 maybe formed with coupling end 22 formed on substantially cylindricalopposite end 20 or formed as a separate component. These and othersuitable methods for securing individual pieces of the multi-piececartridge casing are useful in the practice of the present invention.Coupling end 22 is shown as a male element, but may also be configuredas a female element in alternate embodiments of the invention. In someembodiments the forward end of bullet-end component 18 includes theforward end opening 16 without a shoulder 24 forming chamber neck 26.The bullet-end component typically has a wall thickness between about0.003 and about 0.200 inches and more preferably between about 0.005 andmore preferably between about 0.150 inches about 0.010 and about 0.050inches. The middle body component 28 is substantially cylindrical andconnects the forward end of bullet-end component 18 to the substantiallycylindrical opposite end 20 and forms the propellant chamber 14. Thesubstantially cylindrical opposite end 20 includes a substantiallycylindrical insert 32 that partially seals the propellant chamber 14.The substantially cylindrical insert 32 includes a bottom surface 34located in the propellant chamber 14 that is opposite a top surface (notshown). The substantially cylindrical insert 32 includes a primer recess(not shown) positioned in the top surface (not shown) extending towardthe bottom surface 34 with a primer flash hole aperture (not shown) islocated in the primer recess (not shown) and extends through the bottomsurface 34 into the propellant chamber 14 to combust the propellant inthe propellant chamber 14. A primer (not shown) is located in the primerrecess (not shown) and extends through the bottom surface 34 into thepropellant chamber 14. When molded the coupling end 22 extends thepolymer through the primer flash hole aperture (not shown) to form theprimer flash hole (not shown) while retaining a passage from the topsurface (not shown) through the bottom surface 34 and into thepropellant chamber 14 to provide support and protection about the primerflash hole aperture (not shown). In other embodiments the coupling end22 extends the polymer up to but not into the primer flash hole aperture(not shown) to form the primer flash hole (not shown) while retaining apassage from the top surface (not shown) through the bottom surface 34and into the propellant chamber 14. The bullet-end 18, middle body 28and bottom surface 34 define the interior of propellant chamber 14 inwhich the powder charge (not shown) is contained. The interior volume ofpropellant chamber 14 may be varied to provide the volume necessary forcomplete filling of the propellant chamber 14 by the propellant chosenso that a simplified volumetric measure of propellant can be utilizedwhen loading the cartridge. The bullet-end and bullet components canthen be welded or bonded together using solvent, adhesive, spin-welding,vibration-welding, ultrasonic-welding or laser-welding techniques. Thewelding or bonding increases the joint strength so the casing can beextracted from the hot gun casing after firing at the cook-offtemperature. An optional first and second annular groove (first andsecond cannelures) may be provided in the bullet-end in the interlocksurface of the male coupling element to provide a snap-fit between thetwo components. The cannelures formed in a surface of the bullet at alocation determined to be the optimal seating depth for the bullet. Oncethe bullet is inserted into the casing to the proper depth to lock thebullet in its proper location. One method is the crimping of the entireend of the casing into the cannelures. The bullet-end and middle bodycomponents can then be welded or bonded together using solvent,adhesive, sintering, brazing, soldering, spin-welding,vibration-welding, ultrasonic-welding or laser-welding techniques. Thewelding or bonding increases the joint strength so the casing can beextracted from the hot gun casing after firing at the cook-offtemperature.

Although FIGS. 1a and 1b describes a polymer cartridge the presentinvention also applies to metal cartridges (e.g., made by metalinjection molding, casting, machining, forging, 3-D printing, and anyother mechanism used to make a cartridge) and hybrid cartridges thatinclude a cartridge made from a combination of polymers and metal or anycombination of polymers or copolymers and metals and/or alloys. Thepresent invention may also be used in a traditional metal cartridgecasing. The metal cartridge casing includes a metal casing having apropellant chamber with a forward end opening for insertion of aprojectile. The forward end opening may include a shoulder formingchamber neck. The opposite end of the forward end opening in the metalcartridge casing includes a flange around the parameter and a primerrecess with a primer flash aperture formed therein for ease of insertionof the primer (not shown). A primer flash hole aperture is located inthe primer recess and extends into the propellant chamber to combust thepropellant in the propellant chamber.

FIG. 2 is a general image of a bullet or projectile. For the purpose ofdescription the general projectile shape is shown below as theprojectile 50. The projectile 50 of the present invention includes allshapes and calibers. The present invention is not limited to thedescribed caliber and is believed to be applicable to other calibers aswell. This includes various small and medium caliber munitions,including 5.56 mm, 7.62 mm, 308, 338, 3030, 3006, and .50 caliberammunition cartridges, as well as medium/small caliber ammunition suchas 380 caliber, 38 caliber, 9 mm, 10 mm and military style ammunitionincluding 12.7 mm, 14.5 mm, 14.7 mm, 20 mm, 25 mm, 30 mm, 40 mm, 57 mm,60 mm, 75 mm, 76 mm, 81 mm, 90 mm, 100 mm, 105 mm, 106 mm, 115 mm, 120mm, 122 mm, 125 mm, 130 mm, 152 mm, 155 mm, 165 mm, 175 mm, 203 mm, 460mm, 8 inch, 4.2 inch, 45 caliber and the like. Thus, the presentinvention is also applicable to the sporting goods industry for use byhunters and target shooters as well as military use.

The projectile 50 may have any profile but generally has an aerodynamicstreamlined shape at the head and at the tail, e.g., spritzer, flat basespritzer, boat tail spritzer, tapered-heel spritzer, rounded nose,rounded nose flat base, rounded nose boat tail, rounded nosetapered-heel, flat nose, flat nose flat base, flat nose boat tail, flatnose tapered-heel, hollow point, hollow point boat tail, hollow pointflat base, hollow point tapered-heel and so on. Although any head shapecan be used, more common shapes include spritzer shape, round, conical,frustoconical, blunted, wadcutter, or hollow point, and the more commontail shape includes flat base, boat tail, tapered-heel expanded bases orbanded bases. The bullets of the present invention may have any profileand weight dictated by the particular application. For example, themethod and bullets of the present invention may be used in full metaljacket metal cased and full metal jacket both refer to bullets with ametal coating that covers all of, or all but the base of a bullet; metalcased (e.g., as used by REMINGTON® to refer to their full metal jacketedbullets); hollow point bullets have a concave shaped tip thatfacilitates rapid expansion of the round upon impact; boat tail bulletshave a streamlined base to facilitate better aerodynamics; boat tailhollow point; full metal jacketed boat tail; point jacketed hollow pointbullets are similar in design to regular hollow point bullets, but havea copper jacket that normally covers everything but the hollowed portionof the round; jacketed flat point rounds have a flat area of exposedlead at the tip; jacketed soft point bullets usually have a spirepointed tip of exposed lead. Jacketed spitzer point can refer to ajacketed spitzer point; spitzer meaning a sharply pointed bullet;jacketed round nose jacketed round nose bullets split the differencebetween jacketed flat point and jacketed spitzer point bullets and havea rounded tip of exposed lead boat tail soft point sometimes the lettersin the acronyms are switched, so boat tail soft point may also beabbreviated as soft point boat tail. Expanding full metal jacketedrounds appear as and feed like a regular full metal jacket bullet, buthave a construction that allows the case to collapse and the bullet toflatten upon impact. Wad cutter designs often appear to be nothing morethan a cylinder, usually with a hollow base which is used in targetpractice to punch neat holes in the paper, rather than the ragged holesproduced by more rounded designs. Semi wad cutter bullets have a roundednose that comes down to a cylinder that is slightly larger than therounded section, giving the bullet a more aerodynamic shape whileallowing it to punch clean holes in paper targets. Rounded flat pointbullets have a flat tip that is smaller than the bullet diameter androunded shoulders. Armor piercing ammunition can have bullets with avariety of shapes, though in general they are spire pointed and fullmetal jacketed rounds that have a strong core designed to penetratearmor. Armor piercing incendiary ammunition has the same penetratingabilities of armor piercing bullets, but with the added function ofbursting into an intense flame upon impact. Frangible ammunition isavailable under a number of trademarks; notably MAGSAFE®, GLASER®, andSINTERFIRE® and are characterized by a design that facilitates the rapidbreakup of the bullet upon impact, thus, reducing the chances ofover-penetration or a ricochet. Exploding ammunition includes delayedand aerial/above ground exploding ammunition plus ammunition that canpenetrate an objective and have a delay before exploding afterpenetrating. Also included are jacketed designs where the core materialis a very hard, high-density metal such as tungsten, tungsten carbide,depleted uranium, or steel.

FIG. 2 is an image of a flat nose boattail projectile. The projectile 50includes an ogive 52 that extends from the nose 54 (flat tip) to theshoulder 56. The distance from the nose 54 to the shoulder 56 is thehead or ogive distance 58, with the distance from the shoulder 56extending away from the nose 54 is the bearing surface 60. The bearingsurface 60 may be extended with a boattail 62, which tappers to heal 64that curves to form a base 66. An optional cannelure 68 may bepositioned on the bearing surface 60 below the shoulder 56.

FIG. 3 is an image of an full metal jacket, expanding full metal jacket,spritzer, jacketed spritzer, armor piercing, armor piercing incendiaryor a similar projectile 50 having a pointed nose 55 and a boattail 62.The ogive 52 extends from the pointed nose 55 (pointed tip) to theshoulder 56. The distance from the nose 54 to the shoulder 56 is thehead or ogive distance 58, with the distance from the shoulder 56extending away from the pointed nose 55 is the bearing surface 60. Thebearing surface 60 may be extended with a boattail 62, which tappers toheal 64 that curves to form a base 66. An optional cannelure 68 may bepositioned on the bearing surface 60 below the shoulder 56.

FIG. 4 is an image of a flat nose flat base projectile. The projectile50 includes an ogive 52 that extends from the nose 54 (flat tip) to theshoulder 56. The distance from the nose 54 to the shoulder 56 is thehead or ogive distance 58, with the distance from the shoulder 56extending away from the nose 54 is the bearing surface 60. The bearingsurface 60 ends with a flat base 70. An optional cannelure 68 may bepositioned on the bearing surface 60 below the shoulder 56.

FIG. 5 is an image of an full metal jacket, expanding full metal jacket,spritzer, jacketed spritzer, armor piercing, armor piercing incendiaryor a similar projectile 50 having a pointed nose 55 and a flat base 70.The ogive 52 extends from the pointed nose 55 (pointed tip) to theshoulder 56. The distance from the pointed nose 55 to the shoulder 56 isthe head or ogive distance 58, with the distance from the shoulder 56extending away from the pointed nose 55 is the bearing surface 60. Thebearing surface 60 ends with a flat base 70. An optional cannelure 68may be positioned on the bearing surface 60 below the shoulder 56.

FIG. 6 is an image of a boattail projectile without a cannelure. Theprojectile 50 includes an ogive 52 that extends from the nose 54 to theshoulder 56. The distance from the nose 54 (blunt or pointed (notshown)) to the shoulder 56 is the head or ogive distance 58, with thedistance from the shoulder 56 extending away from the nose 54 is thebearing surface 60. The bearing surface 60 may be extended with aboattail 62, which tappers to heal 64 that curves to form a base 66.

FIG. 7 is an image of a flat base projectile without a cannelure. Theogive 52 extends from the nose 54 (blunt or pointed (not shown)) to theshoulder 56. The distance from the nose 54 to the shoulder 56 is thehead or ogive distance 58, with the distance from the shoulder 56extending away from the nose 54 is the bearing surface 60. The bearingsurface 60 may be extended to flat base 70.

FIG. 8 is an image of a boattail projectile 50 with rounded nose. Theprojectile 50 includes an ogive 52 that extends from the rounded nose 72to the shoulder 56. The distance from the rounded nose 72 to theshoulder 56 is the head or ogive distance 58, with the distance from theshoulder 56 extending away from the nose 72 is the bearing surface 60.The bearing surface 60 may be extended with a boattail 62, which tappersto heal 64 that curves to form a base 66. An optional cannelure 68 maybe positioned on the bearing surface 60 below the shoulder 56.

FIG. 9 is an image of a flat base projectile 50 with a rounded nose 72.The ogive 52 extends from the rounded nose 72 to the shoulder 56. Thedistance from the rounded nose 72 to the shoulder 56 is the head orogive distance 58, with the distance from the shoulder 56 extending awayfrom the rounded nose 72 is the bearing surface 60. The bearing surface60 may be extended to flat base 70. An optional cannelure 68 may bepositioned on the bearing surface 60 below the shoulder 56.

FIG. 10 is an image of a flat base projectile 50 having multiplecannelures 68 a-68 c. The ogive 52 extends from the nose 54 to theshoulder 56. The distance from the nose 54 to the shoulder 56 is thehead or ogive distance 58, with the distance from the shoulder 56extending away from the nose 54 is the bearing surface 60. The bearingsurface 60 terminates in a flat base 70. The cannelures 68 a-68 c may bepositioned on the bearing surface 60 below the shoulder 56. Although 1and 3 cannelures 68 a-68 c are shown as representative examples, anynumber of cannelures may be used, e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 ormore cannelures having various thicknesses and depths.

FIG. 11 is an image of a boattail projectile 50 having multiplecannelures 68 a-68 c. The projectile 50 includes an ogive 52 thatextends from the nose 54 to the shoulder 56. The distance from the nose54 to the shoulder 56 is the head or ogive distance 58, with thedistance from the shoulder 56 extending away from the nose 54 is thebearing surface 60. The bearing surface 60 may be extended with aboattail 62, which tappers to heal 64 that curves to form a base 66.Although 1 and 3 cannelures 68 a-68 c are shown as representativeexamples, any number of cannelures may be used, e.g., 1, 2, 3, 4, 5, 6,7, 8, 9, 10 or more cannelures having various thicknesses and depths.

These projectiles described herein may be made using a metal injectionmolding process. The metal injection molding process, which generallyinvolves mixing fine metal powders with binders to form a feedstock thatis injection molded into a closed mold, may be used to form asubstantially cylindrical insert. After ejection from the mold, thebinders are chemically or thermally removed from the substantiallycylindrical insert so that the part can be sintered to high density.During the sintering process, the individual metal particlesmetallurgically bond together as material diffusion occurs to removemost of the porosity left by the removal of the binder.

FIG. 12 is a cut away image of a jacketed spritzer projectile. Theprojectile 50 includes a nose 55 that extends to a shoulder 56. Abearing surface 60 extends from the shoulder 56 to the base 70. Theouter surface 73 of the projectile 50 is a metal jacket covering a metalcore 74 that includes a spiral ridge 76 a, 76 b and 76 c (alternativelyit may be a spiral groove). In addition, at least a portion of the ogive52 of the outer surface 73 may be of a softer metal to allow deformationat impact allowing the metal core 74 to penetrate the target.

FIG. 13 is a cut away image of a jacketed projectile. The projectile 50includes a nose 55 that extends to a shoulder 56. A bearing surface 60extends from the shoulder 56 to the base 70. The outer surface 73 of theprojectile 50 is a metal jacket covering a metal core 74 thatencompasses a central projectile 78 having ridges or fins 80 a, 80 b and80 c that terminate at a tip 82 (alternatively the central projectile 78may have spiral grooves or ridges). In addition, at least a portion ofthe ogive 52 of the outer surface 73 may be of a softer metal to allowdeformation at impact allowing the metal core 74 to penetrate thetarget.

FIG. 14 is a cut away image of a jacketed projectile. The projectile 50includes a nose 55 that extends to a shoulder 56. A bearing surface 60extends from the shoulder 56 to the base 70. The outer surface 73 of theprojectile 50 is a metal jacket covering a metal core 74 that includeslongitudinal ridges 76 a, 76 b and 76 c (alternatively it may belongitudinal grooves). In addition, at least a portion of the ogive 52of the outer surface 73 may be of a softer metal to allow deformation atimpact allowing the metal core 74 to penetrate the target.

FIG. 15 is a cut away image of a jacketed projectile. The projectile 50includes a nose 55 that extends to a shoulder 56. A bearing surface 60extends from the shoulder 56 to the base 70. The outer surface 73 of theprojectile 50 is a jacket covering a metal core 74 that encompasses acentral projectile 78 that terminate at a tip 82. In addition, at leasta portion of the ogive 52 of the outer surface 73 may be of a softermetal to allow deformation at impact allowing the metal core 74 topenetrate the target.

FIG. 16 is a cut away image of a jacketed projectile. The projectile 50includes a nose 55 that extends to a shoulder 56. A bearing surface 60extends from the shoulder 56 to the base 70. The outer surface 73 of theprojectile 50 is a jacket covering a metal core 74 that encompasses acentral region 84 that terminate at a tip 82. The central region 84 maycontain a flammable composition that is ignited by ignition source 86.

FIG. 17 is a cut away image of a jacketed projectile. The projectile 50includes a nose 55 that extends to a shoulder 56. A bearing surface 60extends from the shoulder 56 to the base 70. The outer surface 73 of theprojectile 50 is a jacket covering a metal core 74 that encompasses acentral region 84 that terminate at a tip 82. The central region 84 maycontain pelleted materials 88 that may be ejected upon impact. Inaddition, at least a portion of the ogive 52 of the outer surface 73 maybe of a softer metal to allow deformation at impact allowing moreefficient ejection of the pelleted materials 88.

FIG. 18 is a cut away image of a jacketed projectile. The projectile 50includes a nose 55 that extends to a shoulder 56. A bearing surface 60extends from the shoulder 56 to the base 70. The outer surface 73 of theprojectile 50 partially covers a central projectile 78 to allow thecentral projectile 78 to penetrate the target.

FIGS. 19a-19s are images of a cut away image of different projectiletypes. FIG. 19a is an image of a projectile 50 that is an armor piercingtracer having a boattail 62 configured end, a tracer element 90 andsolid shot 92. FIG. 19b is an image of a projectile 50 that is an armorpiercing high explosive projectile having a base fuse 94 and highexplosive charge 96. FIG. 19c is an image of a projectile 50 that is anarmor piercing high explosive projectile having a base fuse 94, highexplosive charge 96 and an armor piercing shot 98 and armor piercing cap100. FIG. 19d is an image of a projectile 50 that is a heat shapedcharge projectile having a fuse 102, void space 104 and cavity 106 and ahigh explosive charge 96 surrounding a flash tube 108 connecting thefuse 102 and the booster 110. FIG. 19e is an image of a projectile 50that is an anti-concrete projectile having a ballistic cap 112 housing ablunt nose 114 connected to a base fuse 94 and high explosive charge 96.FIG. 19f is an image of a projectile 50 that is a high-explosive andhigh capacity projectile having a high explosive 50 and a booster 110.FIG. 19g is an image of a projectile 50 that is a shrapnel projectilethat includes a shrapnel projectile having a base ejection mechanism 116and a shrapnel 118. FIG. 19h is an image of a projectile 50 that is acanister projectile having shot 120 disposed in the canister. FIG. 19iis an image of a projectile 50 that is an illuminating projectile thatincludes an ejection charge 122 and an illumination element 124connected to a parachute 126 connected to a suspending cord 128. FIG.19j is an image of a projectile 50 that is an armor piercing capballistic cap projectile having a base fuse 94, high explosive charge 96and an armor piercing shot 98, armor piercing cap 100 and ballistic cap112. FIG. 19k is an image of a projectile 50 that is a high velocityarmor piercing projectile having a tracer element 90 and a light metalcasing 130 over a hard dense core 132. FIG. 19l is an image of aprojectile 50 that is a high velocity armor piercing arrowheadprojectile having a tracer element 90 and a light metal casing 130 overa hard dense core 132. FIG. 19m is an image of a projectile 50 that is ahigh explosive projectile having a fuse 102, high explosive charge 96, atracer element 90 and a rotation band 134. FIG. 19n is an image of aprojectile 50 that is a high explosive chemical projectile having one ormore chemicals 136 with a high explosive charge 96 and a high explosiveburster 140, and a centering band 138. FIG. 190 is an image of aprojectile 50 that is a smoke projectile having one or more smokecompositions 142 and a high explosive burster 140. FIG. 19p is an imageof a projectile 50 that is a discarding sabot projectile having a hardcore 132 covered by a outer shell 144 and a discardable carrier 146.FIG. 19q is an image of a projectile 50 that is a tapered boreprojectile having a bourrelet 148 and a rotating flange 150. FIG. 19r isan image of a projectile 50 that is a rocket assisted projectile havinga high explosive charge 96 and a rocket propellant 152 with venturis154. FIG. 19s is an image of a projectile 50 that is a discarding sabotprojectile having a hard core 132 with one or more fins 156 and adiscardable carrier 146.

FIGS. 20a-20v are images of various projectiles of the presentinvention. FIG. 20a is a perspective view of a round point projectile.FIGS. 20b-20e are side views of a round point projectile. FIGS. 20f-20gare perspectives view of a blunt point projectile. FIGS. 20h-20k areside views of a blunt point projectile. FIG. 201 is a perspective viewof a flat point projectile. FIGS. 20m-20p are side views of a flat pointprojectile. FIG. 20q is a cut through view of a hollow point projectilehaving relief grooves. FIG. 20r is a top view of a hollow pointprojectile having relief grooves. FIG. 20t is a perspective view of ahollow point projectile. FIGS. 20s, 20u and 20v are perspective views ofone embodiment of a projectile of the present invention.

FIG. 21 depicts a side, cross-sectional view of a portion of thepolymeric cartridge case having a two piece primer insert. Thesubstantially cylindrical primer insert 32 has an upper primer insertportion 56 and a lower primer insert portion 58 joined at insert joint60. The upper primer insert portion 56 may be of the same or differentmaterials than lower primer insert portion 58. The upper primer insertportion 56 mates to the lower primer insert portion 58 at insert joint60 while retaining the primer flash hole 40 and the primer recess 38.The insert joint 60 may connect the upper primer insert portion 56 andthe lower primer insert portion 58 by welding or bonding using solvent,adhesive, spin-welding, vibration-welding, ultrasonic-welding orlaser-welding techniques. In addition, multiple methods may be used toincrease the joint strength. The upper primer insert portion 56 includesa substantially cylindrical coupling element 30 extending from a bottomsurface 34 that is opposite a top surface 36. The coupling element 30extends with a taper to a smaller diameter at the tip 44. Located in thetop surface 36 is a primer recess 38 that extends toward the bottomsurface 34. A primer flash hole 40 is located in the primer recess 38and extends through the bottom surface 34 into the propellant chamber14. The coupling end 22 of the middle body extends the polymer throughthe primer flash hole 40 to form an aperture coating 42 while retaininga passage from the top surface 36 through the bottom surface 34 and intothe propellant chamber 14 to provide support and protection about theprimer flash hole 40. When over-molded the coupling end 22 interlockswith the substantially cylindrical coupling element 30. The couplingelement 30 extends with a taper to a smaller diameter at the tip 44 tophysical interlock the substantially cylindrical insert 32 to the middlebody component. The substantially cylindrical insert 32 includes asubstantially cylindrical coupling element 30 extending from a bottomsurface 34 that is opposite a top surface 36. Located in the top surface36 is a primer recess 38 that extends toward the bottom surface 34. Aprimer flash hole 40 is located in the primer recess 38 and extendsthrough the bottom surface 34 into the propellant chamber 14. Thecoupling end 22 extends the polymer through the primer flash hole 40 toform an aperture coating 42 while retaining a passage from the topsurface 36 through the bottom surface 34 and into the propellant chamber14 to provide support and protection about the primer flash hole 40.When contacted the coupling end 22 interlocks with the substantiallycylindrical coupling element 30, through the coupling element 30 thatextends with a taper to a smaller diameter at the tip 44 to physicalinterlock the substantially cylindrical insert 32 and the middle bodycomponent 28.

The present invention also provides MIMs of spin-stabilized projectiles.Spinning a projectile promotes flight stability. Spinning is obtained byfiring the projectiles through a rifled tube. The projectile engages therifling by means of a rotating band normally made of copper. Therotating band is engaged by the lands and grooves. At a nominal muzzlevelocity of 2,800 feet per second, spin rates on the order of 250revolutions per second are encountered. Spin-stabilized projectiles arefull bore (flush with the bore walls) and are limited approximately to a5:1 length-to-diameter ratio. They perform very well at relatively lowtrajectories (less than 45 quadrant elevation). In high trajectoryapplications they tend to overstabilize (maintain the angle at whichthey were fired) and, therefore, do not follow the trajectorysatisfactorily so other rations may be used to account for this.

The present invention also provides MIMs of fin-stabilized projectilesto obtain stability through the use of fins located at the aft end ofthe projectile. Normally, four to six fins are employed. Additionalstability is obtained by imparting some spin (approximately 20revolutions/second) to the projectile by canting the leading edge of thefins. Fin-stabilized projectiles are very often subcaliber. A sabot,wood or metal fitted around the projectile, is used to center theprojectile in the bore and provide a gas seal. Such projectiles varyfrom 10:1 to 15:1 in length-to-diameter ratio. Fin-stabilizedprojectiles are advantageous because they follow the trajectory verywell at high-launch angles, and they can be designed with very low dragthereby increasing range and/or terminal velocity.

The present invention also provides MIMs of rocket-assisted projectilesto extend the range over standard gun systems and to allow for lightermount and barrel design and reduce excessive muzzle flash and smoke byreducing the recoil and setback forces of standard gun systems. Sincethe ranges are different, the above two objectives represent oppositeapproaches in the development of rocket-assisted projectiles. Normally,one or the other establishes the performance of the rocket-assistedprojectile under development although some compromise in the twoapproaches may be established by the design objectives.

The raw materials for metal injection molding are metal powders and athermoplastic binder. There are at least two Binders included in theblend, a primary binder and a secondary binder. This blended powder mixis worked into the plasticized binder at elevated temperature in akneader or shear roll extruder. The intermediate product is theso-called feedstock. It is usually granulated with granule sizes ofseveral millimeters. In metal injection molding, only the binders areheated up, and that is how the metal is carried into the projectileshaped mold cavity.

Projectiles are molded by filling the mold cavity. Both mold designfactors such as runner and gate size, gate placement, venting andmolding parameters set on the molding machine affect the molded part. Ahelium Pycnometer can determine if there are voids trapped inside theparts. During molding, tool that can be used to measure the percent oftheoretical density achieved on the “Green” or molded part. By crushingthe measured “Green” molded part back to powder, you can now confirm thepercent of air (or voids) trapped in the molded part. To measure this,the density of the molded part should be measured in the heliumPycnometer and compared to the theoretical density of the feedstock.Then, take the same molded part that was used in the density test andcrush it back to powder. If this granulate shows a density of more than100% of that of the feedstock, then some of the primary binders havebeen lost during the molding process. The molding process needs to becorrected because using this process with a degraded feedstock willresult in a larger shrinkage and result in a part smaller than thatdesired. It is vital to be sure that your molded parts are completelyfilled before continuing the manufacturing process for debinding andsintering. The helium Pycnometer provides this assurance. Primarydebinding properly debound parts are extremely important to establishthe correct sintering profile. The primary binder must be completelyremoved before attempting to start to remove the secondary binder as thesecondary binder will travel through the pores created by the extractionof the primary binder. Primary debinding techniques depend on thefeedstock type used to make the parts. However, the feedstock supplierknows the amount of primary binders that have been added and should beremoved before proceeding to the next process step. The feedstocksupplier provides a minimum “brown density” that must be achieved beforethe parts can be moved into a furnace for final debinding and sintering.This minimum brown density will take into account that a small amount ofthe primary binder remnant may be present and could be removed by asuitable hold during secondary debinding and sintering. The sinteringprofile should be adjusted to remove the remaining small percent ofprimary binder before the removal of the secondary binder. Most externalfeedstock manufacturers provide only a weight loss percent that shouldbe obtained to define suitable debinding. Solvent debound parts must bethoroughly dried, before the helium Pycnometer is used to determine the“brown” density so that the remnant solvent in the part does not affectthe measured density value. When the feedstock manufacturer gives youthe theoretical density of the “brown” or debound part, can validate thepercent of debinding that has been achieved. Most Metal InjectionMolding (MIM) operations today perform the secondary debinding andsintering in the same operation. Every MIM molder has gates and runnersleft over from molding their parts. So, you will be able to now re-useyour gates and runners with confidence that they will shrink correctlyafter sintering. If the feedstock producers have given you the actualand theoretical densities of their feedstock, you can easily measure thedensities of the gates and runners and compare the results to the valuessupplied. Once the regrind densities are higher than that required tomaintain the part dimensions, the regrinds are no longer reusable.

Feedstock in accordance with the present invention may be prepared byblending the powdered metal with the binder and heating the blend toform a slurry. Uniform dispersion of the powdered metal in the slurrymay be achieved by employing high shear mixing. The slurry may then becooled to ambient temperature and then granulated to provide thefeedstock for the metal injection molding.

The amount of powdered metal and binder in the feedstock may be selectedto optimize moldability while insuring acceptable green densities. Inone embodiment, the feedstock used for the metal injection moldingportion of the invention may include at least about 40 percent by weightpowdered metal, in another about 50 percent by weight powdered metal ormore. In one embodiment, the feedstock includes at least about 60percent by weight powdered metal, preferably about 65 percent by weightor more powdered metal. In yet another embodiment, the feedstockincludes at least about 75 percent by weight powdered metal. In yetanother embodiment, the feedstock includes at least about 80 percent byweight powdered metal. In yet another embodiment, the feedstock includesat least about 85 percent by weight powdered metal. In yet anotherembodiment, the feedstock includes at least about 90 percent by weightpowdered metal.

The binding agent may be any suitable binding agent that does notdestroy or interfere with the powdered metals. The binder may be presentin an amount of about 50 percent or less by weight of the feedstock. Inone embodiment, the binder is present in an amount ranging from 10percent to about 50 percent by weight. In another embodiment, the binderis present in an amount of about 25 percent to about 50 percent byweight of the feedstock. In another embodiment, the binder is present inan amount of about 30 percent to about 40 percent by weight of thefeedstock. In one embodiment, the binder is an aqueous binder. Inanother embodiment, the binder is an organic-based binder. Examples ofbinders include, but are not limited to, thermoplastic resins, waxes,and combinations thereof. Non-limiting examples of thermoplastic resinsinclude polyolefins such as acrylic polyethylene, polypropylene,polystyrene, polyvinyl chloride, polyethylene carbonate, polyethyleneglycol, and mixtures thereof. Suitable waxes include, but are notlimited to, microcrystalline wax, bee wax, synthetic wax, andcombinations thereof.

Examples of suitable powdered metals for use in the feedstock include,but are not limited to: stainless steel including martensitic andaustenitic stainless steel, steel alloys, tungsten alloys, soft magneticalloys such as iron, iron-silicon, electrical steel, iron-nickel(50Ni-50F3), low thermal expansion alloys, or combinations thereof. Inone embodiment, the powdered metal is a mixture of stainless steel,brass and tungsten alloy. The stainless steel used in the presentinvention may be any 1 series carbon steels, 2 series nickel steels, 3series nickel-chromium steels, 4 series molybdenum steels, serieschromium steels, 6 series chromium-vanadium steels, 7 series tungstensteels, 8 series nickel-chromium-molybdenum steels, or 9 seriessilicon-manganese steels, e.g., 102, 174, 201, 202, 300, 302, 303, 304,308, 309, 316, 316L, 316Ti, 321, 405, 408, 409, 410, 416, 420, 430, 439,440, 446 or 601-665 grade stainless steel.

As known to those of ordinary skill in the art, stainless steel is analloy of iron and at least one other component that imparts corrosionresistance. As such, in one embodiment, the stainless steel is an alloyof iron and at least one of chromium, nickel, silicon, molybdenum, ormixtures thereof. Examples of such alloys include, but are not limitedto, an alloy containing about 1.5 to about 2.5 percent nickel, no morethan about 0.5 percent molybdenum, no more than about 0.15 percentcarbon, and the balance iron with a density ranging from about 7 g/cm³to about 8 g/cm³; an alloy containing about 6 to about 8 percent nickel,no more than about 0.5 percent molybdenum, no more than about 0.15percent carbon, and the balance iron with a density ranging from about 7g/cm³ to about 8 g/cm³; an alloy containing about 0.5 to about 1 percentchromium, about 0.5 percent to about 1 percent nickel, no more thanabout 0.5 percent molybdenum, no more than about 0.2 percent carbon, andthe balance iron with a density ranging from about 7 g/cm³ to about 8g/cm³; an alloy containing about 2 to about 3 percent nickel, no morethan about 0.5 percent molybdenum, about 0.3 to about 0.6 percentcarbon, and the balance iron with a density ranging from about 7 g/cm³to about 8 g/cm³; an alloy containing about 6 to about 8 percent nickel,no more than about 0.5 percent molybdenum, about 0.2 to about 0.5percent carbon, and the balance iron with a density ranging from about 7g/cm³ to about 8 g/cm³; an alloy containing about 1 to about 1.6 percentchromium, about 0.5 percent or less nickel, no more than about 0.5percent molybdenum, about 0.9 to about 1.2 percent carbon, and thebalance iron with a density ranging from about 7 g/cm³ to about 8 g/cm³;and combinations thereof.

Suitable tungsten alloys include an alloy containing about 2.5 to about3.5 percent nickel, about 0.5 percent to about 2.5 percent copper oriron, and the balance tungsten with a density ranging from about 17.5g/cm³ to about 18.5 g/cm³; about 3 to about 4 percent nickel, about 94percent tungsten, and the balance copper or iron with a density rangingfrom about 17.5 g/cm³ to about 18.5 g/cm³; and mixtures thereof.

In addition, the binders may contain additives such as antioxidants,coupling agents, surfactants, elasticizing agents, dispersants, andlubricants as disclosed in U.S. Pat. No. 5,950,063, which is herebyincorporated by reference in its entirety. Suitable examples ofantioxidants include, but are not limited to thermal stabilizers, metaldeactivators, or combinations thereof. In one embodiment, the binderincludes about 0.1 to about 2.5 percent by weight of the binder of anantioxidant. Coupling agents may include but are not limited totitanate, aluminate, silane, or combinations thereof. Typical levelsrange between 0.5 and 15% by weight of the binder.

For example, the metal injection molding process, which generallyinvolves mixing fine metal powders with binders to form a feedstock thatis injection molded into a closed mold, may be used to form asubstantially cylindrical insert. After ejection from the mold, thebinders are chemically or thermally removed from the substantiallycylindrical insert so that the part can be sintered to high density.During the sintering process, the individual metal particlesmetallurgically bond together as material diffusion occurs to removemost of the porosity left by the removal of the binder.

The raw materials for metal injection molding are metal powders and athermoplastic binder. There are at least two binders included in theblend, a primary binder and a secondary binder. This blended powder mixis worked into the plasticized binder at elevated temperature in akneader or shear roll extruder. The intermediate product is theso-called feedstock. It is usually granulated with granule sizes ofseveral millimeters. In metal injection molding, only the binders areheated up, and that is how the metal is carried into the mold cavity.

In preparing a feedstock, it is important first to measure the actualdensity of each lot of both the metal powders and binders. This isextremely important especially for the metal powders in that each lotwill be different based on the actual chemistry of that grade of powder.For example, 316L is comprised of several elements, such as Fe, Cr, Ni,Cu, Mo, P, Si, S and C. In order to be rightfully called a 316L, each ofthese elements must meet a minimum and maximum percentage weightrequirement as called out in the relevant specification. Hence thevariation in the chemistry within the specification results in asignificant density variation within the acceptable composition range.Depending on the lot received from the powder producer, the density willvary depending on the actual chemistry received.

In preparing a feedstock, it is important first to measure the actualdensity of each lot of both the metal powders and binders. This isextremely important especially for the metal powders in that each lotwill be different based on the actual chemistry of that grade of powder.For example, 316L is comprised of several elements, such as Fe, Cr, Ni,Cu, Mo, P, Si, S and C. In order to be rightfully called a 316L, each ofthese elements must meet a minimum and maximum percentage weightrequirement as called out in the relevant specification. Tables I-IVbelow provide other examples of the elemental compositions of some ofthe metal powders, feed stocks, metals, alloys and compositions of thepresent invention. Hence the variation in the chemistry within thespecification results in a significant density variation within theacceptable composition range. Depending on the lot received from thepowder producer, the density will vary depending on the actual chemistryreceived.

TABLE I Material Chemical Composition, % - Low-Alloy Steels DesignationCode Fe Ni Mo C Si (max) MIM-2200⁽¹⁾ Bal. 1.5-2.5 0.5 max 0.1 max 1.0MIM-2700 Bal. 6.5-8.5 0.5 max 0.1 max 1.0 MIM-4605⁽²⁾ Bal. 1.5-2.50.2-0.5 0.4-0.6 1.0

TABLE II Material Designation Chemical Composition, % - Stainless SteelsCode Fe Ni Cr Mo C Cu Nb + Ta Mn (max) Si (max) MIM-316L Bal. 10-1416-18 2-3 0.03 max — — 2.0 1.0 MIM-420 Bal. — 12-14 — 0.15-0.4 — — 1.01.0 MIM-430L Bal. — 16-18 — 0.05 max — — 1.0 1.0 MIM-17-4 PH Bal. 3-515.5-17.5 — 0.07 max 3-5 0.15-0.45 1.0 1.0

TABLE III Material Designation Chemical Composition, % - Soft-MagneticAlloys Code Fe Ni Cr Co Si C (max) Mn V MIM-2200 Bal. 1.5-2.5 — — 1.0max 0.1 — — MIM-Fe - 3% Si Bal. — — — 2.5-3.5 0.05 — — MIM-Fe50% Ni Bal.49-51 — — 1.0 max 0.05 — — MIM-Fe50% Co Bal. — — 48-50 1.0 max 0.05 —2.5 max MIM-430L Bal. — 16-18 — 1.0 max 0.05 1.0 max —

TABLE IV Nominal Chemical Composition, % - Controlled-Expansion AlloysMaterial Mn Si C Al Mg Zr Ti Cu Cr Mo Designation Fe Ni Co max max maxmax max max max max max max MIM-F15 Bal. 29 17 0.50 0.20 0.04 0.10 0.100.10 0.10 0.20 0.20 0.20

In addition to the specific compositions listed herein, the skillartisan recognizes the elemental composition of common commercialdesignations used by feedstock manufacturers and processors, e.g.,C-0000 Copper and Copper Alloys; CFTG-3806-K Diluted Bronze Bearings;CNZ-1818 Copper and Copper Alloys; CNZP-1816 Copper and Copper Alloys;CT-1000 Copper and Copper Alloys; CT-1000-K Bronze Bearings; CTG-1001-KBronze Bearings; CTG-1004-K Bronze Bearings; CZ-1000 Copper and CopperAlloys; CZ-2000 Copper and Copper Alloys; CZ-3000 Copper and CopperAlloys; CZP-1002 Copper and Copper Alloys; CZP-2002 Copper and CopperAlloys; CZP-3002 Copper and Copper Alloys; F-0000 Iron and Carbon Steel;F-0000-K Iron and Iron-Carbon Bearings; F-0005 Iron and Carbon Steel;F-0005-K Iron and Iron-Carbon Bearings; F-0008 Iron and Carbon Steel;F-0008-K Iron and Iron-Carbon Bearings; FC-0200 Iron-Copper and CopperSteel; FC-0200-K Iron-Copper Bearings; FC-0205 Iron-Copper and CopperSteel; FC-0205-K Iron-Copper-Carbon Bearings; FC-0208 Iron-Copper andCopper Steel; FC-0208-K Iron-Copper-Carbon Bearings; FC-0505 Iron-Copperand Copper Steel; FC-0508 Iron-Copper and Copper Steel; FC-0508-KIron-Copper-Carbon Bearings; FC-0808 Iron-Copper and Copper Steel;FC-1000 Iron-Copper and Copper Steel; FC-1000-K Iron-Copper Bearings;FC-2000-K Iron-Copper Bearings; FC-2008-K Iron-Copper-Carbon Bearings;FCTG-3604-K Diluted Bronze Bearings; FD-0200 Diffusion-Alloyed Steel;FD-0205 Diffusion-Alloyed Steel; FD-0208 Diffusion-Alloyed Steel;FD-0400 Diffusion-Alloyed Steel; FD-0405 Diffusion-Alloyed Steel;FD-0408 Diffusion-Alloyed Steel; FF-0000 Soft-Magnetic Alloys; FG-0303-KIron-Graphite Bearings; FG-0308-K Iron-Graphite Bearings; FL-4005Prealloyed Steel; FL-4205 Prealloyed Steel; FL-4400 Prealloyed Steel;FL-4405 Prealloyed Steel; FL-4605 Prealloyed Steel; FL-4805 PrealloyedSteel; FL-48105 Prealloyed Steel; FL-4905 Prealloyed Steel; FL-5208Prealloyed Steel; FL-5305 Prealloyed Steel; FLC-4608 Sinter-HardenedSteel; FLC-4805 Sinter-Hardened Steel; FLC-48108 Sinter-Hardened Steel;FLC-4908 Sinter-Hardened Steel; FLC2-4808 Sinter-Hardened Steel;FLDN2-4908 Diffusion-Alloyed Steel; FLDN4C2-4905 Diffusion-AlloyedSteel; FLN-4205 Hybrid Low-Alloy Steel; FLN-48108 Sinter-Hardened Steel;FLN2-4400 Hybrid Low-Alloy Steel; FLN2-4405 Hybrid Low-Alloy Steel;FLN2-4408 Sinter-Hardened Steel; FLN2C-4005 Hybrid Low-Alloy Steel;FLN4-4400 Hybrid Low-Alloy Steel; FLN4-4405 Hybrid Low-Alloy Steel;FLN4-4408 Sinter Hardened Steel; FLN4C-4005 Hybrid Low-Alloy Steel;FLN6-4405 Hybrid Low-Alloy Steel; FLN6-4408 Sinter-Hardened Steel;FLNC-4405 Hybrid Low-Alloy Steel; FLNC-4408 Sinter-Hardened Steel;FN-0200 Iron-Nickel and Nickel Steel; FN-0205 Iron-Nickel and NickelSteel; FN-0208 Iron-Nickel and Nickel Steel; FN-0405 Iron-Nickel andNickel Steel; FN-0408 Iron-Nickel and Nickel Steel; FN-5000Soft-Magnetic Alloys; FS-0300 Soft-Magnetic Alloys; FX-1000Copper-Infiltrated Iron and Steel; FX-1005 Copper-Infiltrated Iron andSteel; FX-1008 Copper-Infiltrated Iron and Steel; FX-2000Copper-Infiltrated Iron and Steel; FX-2005 Copper-Infiltrated Iron andSteel; FX-2008 Copper-Infiltrated Iron and Steel; FY-4500 Soft-MagneticAlloys; FY-8000 Soft-Magnetic Alloys; P/F-1020 Carbon Steel PF; P/F-1040Carbon Steel PF; P/F-1060 Carbon Steel PF; P/F-10C40 Copper Steel PF;P/F-10050 Copper Steel PF; P/F-10060 Copper Steel PF; P/F-1140 CarbonSteel PF; P/F-1160 Carbon Steel PF; P/F-11C40 Copper Steel PF; P/F-11050Copper Steel PF; P/F-11060 Copper Steel PF; P/F-4220 Low-Alloy P/F-42XXSteel PF; P/F-4240 Low-Alloy P/F-42XX Steel PF; P/F-4260 Low-AlloyP/F-42XX Steel PF; P/F-4620 Low-Alloy P/F-46XX Steel PF; P/F-4640Low-Alloy P/F-46XX Steel PF; P/F-4660 Low-Alloy P/F-46XX Steel PF;P/F-4680 Low-Alloy P/F-46XX Steel PF; SS-303L Stainless Steel—300 SeriesAlloy; SS-303N1 Stainless Steel—300 Series Alloy; SS-303N2 StainlessSteel—300 Series Alloy; SS-304H Stainless Steel—300 Series Alloy;SS-304L Stainless Steel—300 Series Alloy; SS-304N1 Stainless Steel—300Series Alloy; SS-304N2 Stainless Steel—300 Series Alloy; SS-316HStainless Steel—300 Series Alloy; SS-316L Stainless Steel—300 SeriesAlloy; SS-316N1 Stainless Steel—300 Series Alloy; SS-316N2 StainlessSteel—300 Series Alloy; SS-409L Stainless Steel—400 Series Alloy;SS-409LE Stainless Steel—400 Series Alloy; SS-410 Stainless Steel—400Series Alloy; SS-410L Stainless Steel—400 Series Alloy; SS-430LStainless Steel—400 Series Alloy; SS-430N2 Stainless Steel—400 SeriesAlloy; SS-434L Stainless Steel—400 Series Alloy; SS-434LCb StainlessSteel—400 Series Alloy; and SS-434N2 Stainless Steel—400 Series Alloy.

Titanium alloys that may be used in this invention include any alloy ormodified alloy known to the skilled artisan including titanium grades5-38 and more specifically titanium grades 5, 9, 18, 19, 20, 21, 23, 24,25, 28, 29, 35, 36 or 38. Grades 5, 23, 24, 25, 29, 35, or 36 annealedor aged; Grades 9, 18, 28, or 38 cold-worked and stress-relieved orannealed; Grades 9, 18, 23, 28, or 29 transformed-beta condition; andGrades 19, 20, or 21 solution-treated or solution-treated and aged.Grade 5, also known as Ti6Al4V, Ti-6Al-4V or Ti 6-4, is the mostcommonly used alloy. It has a chemical composition of 6% aluminum, 4%vanadium, 0.25% (maximum) iron, 0.2% (maximum) oxygen, and the remaindertitanium. It is significantly stronger than commercially pure titaniumwhile having the same stiffness and thermal properties (excludingthermal conductivity, which is about 60% lower in Grade 5 Ti than in CPTi); Grade 6 contains 5% aluminum and 2.5% tin. It is also known asTi-5Al-2.5Sn. This alloy has good weldability, stability and strength atelevated temperatures; Grade 7 and 7H contains 0.12 to 0.25% palladium.This grade is similar to Grade 2. The small quantity of palladium addedgives it enhanced crevice corrosion resistance at low temperatures andhigh pH; Grade 9 contains 3.0% aluminum and 2.5% vanadium. This grade isa compromise between the ease of welding and manufacturing of the “pure”grades and the high strength of Grade 5; Grade 11 contains 0.12 to 0.25%palladium; Grade 12 contains 0.3% molybdenum and 0.8% nickel; Grades 13,14, and 15 all contain 0.5% nickel and 0.05% ruthenium; Grade 16contains 0.04 to 0.08% palladium; Grade 16H contains 0.04 to 0.08%palladium; Grade 17 contains 0.04 to 0.08% palladium; Grade 18 contains3% aluminum, 2.5% vanadium and 0.04 to 0.08% palladium; Grade 19contains 3% aluminum, 8% vanadium, 6% chromium, 4% zirconium, and 4%molybdenum; Grade 20 contains 3% aluminum, 8% vanadium, 6% chromium, 4%zirconium, 4% molybdenum and 0.04% to 0.08% palladium; Grade 21 contains15% molybdenum, 3% aluminum, 2.7% niobium, and 0.25% silicon; Grade 23contains 6% aluminum, 4% vanadium, 0.13% (maximum) Oxygen; Grade 24contains 6% aluminum, 4% vanadium and 0.04% to 0.08% palladium. Grade 25contains 6% aluminum, 4% vanadium and 0.3% to 0.8% nickel and 0.04% to0.08% palladium; Grades 26, 26H, and 27 all contain 0.08 to 0.14%ruthenium; Grade 28 contains 3% aluminum, 2.5% vanadium and 0.08 to0.14% ruthenium; Grade 29 contains 6% aluminum, 4% vanadium and 0.08 to0.14% ruthenium; Grades 30 and 31 contain 0.3% cobalt and 0.05%palladium; Grade 32 contains 5% aluminum, 1% tin, 1% zirconium, 1%vanadium, and 0.8% molybdenum; Grades 33 and 34 contain 0.4% nickel,0.015% palladium, 0.025% ruthenium, and 0.15% chromium; Grade 35contains 4.5% aluminum, 2% molybdenum, 1.6% vanadium, 0.5% iron, and0.3% silicon; Grade 36 contains 45% niobium; Grade 37 contains 1.5%aluminum; and Grade 38 contains 4% aluminum, 2.5% vanadium, and 1.5%iron. Its mechanical properties are very similar to Grade 5, but hasgood cold workability similar to grade 9. One embodiment includes aTi6Al4V composition. One embodiment includes a composition having 3-12%aluminum, 2-8% vanadium, 0.1-0.75% iron, 0.1-0.5% oxygen, and theremainder titanium. More specifically, about 6% aluminum, about 4%vanadium, about 0.25% iron, about 0.2% oxygen, and the remaindertitanium. For example, one Ti composition may include 10 to 35% Cr, 0.05to 15% Al, 0.05 to 2% Ti, 0.05 to 2% Y₂O₅, with the balance being eitherFe, Ni or Co, or an alloy consisting of 20±1.0% Cr, 4.5±0.5% Al,0.5±0.1% Y₂O₅ or ThO2, with the balance being Fe. For example, one Ticomposition may include 15.0-23.0% Cr, 0.5-2.0% Si, 0.0-4.0% Mo,0.0-1.2% Nb, 0.0-3.0% Fe, 0.0-0.5% Ti, 0.0-0.5% Al, 0.0-0.3% Mn,0.0-0.1% Zr, 0.0-0.035% Ce, 0.005-0.025% Mg, 0.0005-0.005% B, 0.005-0.3%C, 0.0-20.0% Co, balance Ni. Sample Ti-based feedstock componentincludes 0-45% metal powder; 15-40% binder; 0-10% Polymer (e.g.,thermoplastics and thermosets); surfactant 0-3%; lubricant 0-3%;sintering aid 0-1%. Another sample Ti-based feedstock component includesabout 62% TiH2 powder as a metal powder; about 29% naphthalene as abinder; about 2.1-2.3% polymer (e.g., EVA/epoxy); about 2.3% SURFONICN-100® as a Surfactant; lubricant is 1.5% stearic acid as; about 0.4%silver as a sintering Aid. Examples of metal compounds include metalhydrides, such as TiH2, and intermetallics, such as TiAl and TiAl₃. Aspecific instance of an alloy includes Ti-6Al,4V, among others. Inanother embodiment, the metal powder comprises at least approximately45% of the volume of the feedstock, while in still another, it comprisesbetween approximately 54.6% and 70.0%. In addition, Ti—Al alloys mayconsists essentially of 32-38% of Al and the balance of Ti and contains0.005-0.20% of B, and the alloy which essentially consists of the abovequantities of Al and Ti and contains, in addition to the above quantityof B, up to 0.2% of C, up to 0.3% of O and/or up to 0.3% of N (providedthat 0+N add up to 0.4%) and c) 0.05-3.0% of Ni and/or 0.05-3.0% of Si,and the balance of Ti.

Both mold design factors such as runner and gate size, gate placement,venting and molding parameters set on the molding machine affect themolded part. A helium Pycnometer can determine if there are voidstrapped inside the parts. During molding, you have a tool that can beused to measure the percent of theoretical density achieved on the“Green” or molded part. By crushing the measured “green” molded partback to powder, you can now confirm the percent of air (or voids)trapped in the molded part. To measure this, the density of the moldedpart should be measured in the helium Pycnometer and compared to thetheoretical density of the feedstock. Then, take the same molded partthat was used in the density test and crush it back to powder. If thisgranulate shows a density of more than 100% of that of the feedstock,then some of the primary binders have been lost during the moldingprocess. The molding process needs to be corrected because using thisprocess with a degraded feedstock will result in a larger shrinkage andresult in a part smaller than that desired. It is vital to be sure thatyour molded parts are completely filled before continuing themanufacturing process for debinding and sintering. The helium Pycnometerprovides this assurance. Primary debinding properly debound parts areextremely important to establish the correct sintering profile. Theprimary binder must be completely removed before attempting to start toremove the secondary binder as the secondary binder will travel throughthe pores created by the extraction of the primary binder. Primarydebinding techniques depend on the feedstock type used to make theparts. However the feedstock supplier knows the amount of primarybinders that have been added and should be removed before proceeding tothe next process step. The feedstock supplier provides a minimum “browndensity” that must be achieved before the parts can be moved into afurnace for final debinding and sintering. This minimum brown densitywill take into account that a small amount of the primary binder remnantmay be present and could be removed by a suitable hold during secondarydebinding and sintering. The sintering profile should be adjusted toremove the remaining small percent of primary binder before the removalof the secondary binder. Most external feedstock manufacturers provideonly a weight loss percent that should be obtained to define suitabledebinding. Solvent debound parts must be thoroughly dried, before thehelium Pycnometer is used to determine the “brown” density so that theremnant solvent in the part does not affect the measured density value.When the feedstock manufacturer gives you the theoretical density of the“brown” or debound part, can validate the percent of debinding that hasbeen achieved. Most MIM operations today perform the secondary debindingand sintering in the same operation. Every MIM molder has gates andrunners left over from molding their parts. So, you will be able to nowre-use your gates and runners with confidence that they will shrinkcorrectly after sintering. If the feedstock producers have given you theactual and theoretical densities of their feedstock, you can easilymeasure the densities of the gates and runners and compare the resultsto the values supplied. Once the regrind densities are higher than thatrequired to maintain the part dimensions, the regrinds are no longerreusable.

For example, one Ti composition may include 10 to 35% Cr, 0.05 to 15%Al, 0.05 to 2% Ti, 0.05 to 2% Y₂O₅, with the balance being either Fe, Nior Co, or an alloy consisting of 20±1.0% Cr, 4.5±0.5% Al, 0.5±0.1% Y₂O₅or ThO₂, with the balance being Fe. For example, one Ti composition mayinclude 15.0-23.0% Cr, 0.5-2.0% Si, 0.0-4.0% Mo, 0.0-1.2% Nb, 0.0-3.0%Fe, 0.0-0.5% Ti, 0.0-0.5% Al, 0.0-0.3% Mn, 0.0-0.1% Zr, 0.0-0.035% Ce,0.005-0.025% Mg, 0.0005-0.005% B, 0.005-0.3% C, 0.0-20.0% Co, balanceNi. Sample Ti-based feedstock component includes 0-45% metal powder;15-40% binder; 0-10% Polymer (e.g., thermoplastics and thermosets);surfactant 0-3%; lubricant 0-3%; sintering aid 0-1%. Another sampleTi-based feedstock component includes about 62% TiH₂ powder as a metalpowder; about 29% naphthalene as a binder; about 2.1-2.3% polymer (e.g.,EVA/epoxy); about 2.3% SURFONIC N-100® as a Surfactant; lubricant is1.5% stearic acid as a; about 0.4% silver as a sintering Aid. Examplesof metal compounds include metal hydrides, such as TiH₂, andintermetallics, such as TiAl and TiAl₃. A specific instance of an alloyincludes Ti-6Al,4V, among others. In another embodiment, the metalpowder comprises at least approximately 45% of the volume of thefeedstock, while in still another, it comprises between approximately54.6% and 70.0%. In addition, Ti—Al alloys may consists essentially of32-38% of Al and the balance of Ti and contains 0.005-0.20% of B, andthe alloy which essentially consists of the above quantities of Al andTi and contains, in addition to the above quantity of B, up to 0.2% ofC, up to 0.3% of O and/or up to 0.3% of N (provided that O+N add up to0.4%) and c) 0.05-3.0% of Ni and/or 0.05-3.0% of Si, and the balance ofTi.

Feedstock in accordance with the present invention may be prepared byblending the powdered metal with the binder and heating the blend toform a slurry. Uniform dispersion of the powdered metal in the slurrymay be achieved by employing high shear mixing. The slurry may then becooled to ambient temperature and then granulated to provide thefeedstock for the metal injection molding.

One embodiment of the powdered metal may include a composition where Nimay be 2.0, 2.25, 2.50, 2.75, 3.0, 3.25, 3.5, 3.75, 4.0, 4.25, 4.50,4.75, 5.0, 5.25, 5.5, 5.75, 6.0, 6.25, 6.50, 6.75, 7.0, 7.25, 7.5, 7.75,8.0, 8.25, 8.50, 8.75, 9.0, 9.25, 9.5, 9.75, 10.0, 10.25, 10.50, 10.75,11.0, 11.25, 11.5, 11.75, 12.0, 12.25, 12.50, 12.75, 13.0, 13.25, 13.5,13.75, 14.0, 14.25, 14.50, 14.75, 15.0, 15.25, 15.5, 15.75, 16.0, 16.25,16.50, 16.75, or 17.0%; Cr may be 9.0, 9.25, 9.5, 9.75, 10.0, 10.25,10.50, 10.75, 11.0, 11.25, 11.5, 11.75, 12.0, 12.25, 12.50, 12.75, 13.0,13.25, 13.5, 13.75, 14.0, 14.25, 14.50, 14.75, 15.0, 15.25, 15.5, 15.75,16.0, 16.25, 16.50, 16.75, 17.0, 17.25, 17.5, 17.75, 18.0, 18.25, 18.50,18.75, 19.0, 19.25, 19.5, 19.75, or 20.0%; Mo may be 0.00, 0.025, 0.050,0.075, 0.10, 0.125, 0.150, 0.175, 0.20, 0.225, 0.250, 0.275, 0.30,0.325, 0.350, 0.375, 0.40, 0.425, 0.450, 0.475, 0.50, 0.525, 0.550,0.575, 0.60, 0.625, 0.650, 0.675, 0.70, 0.725, 0.750, 0.775, 0.80,0.825, 0.850, 0.875, 0.90, 0.925, 0.950, 1.0, 1.25, 1.5, 1.75, 2.0,2.25, 2.50, 2.75, 3.0, 3.25, 3.5, 3.75, 4.0, 4.25, 4.50, 4.75, 5.0,5.25, 5.5, 5.75, 6.0, 6.25, 6.50, 6.75, or 7.0%; C may be 0.00, 0.025,0.050, 0.075, 0.10, 0.125, 0.150, 0.175, 0.20, 0.225, 0.250, 0.275,0.30, 0.325, 0.350, 0.375, 0.40, 0.425, 0.450, 0.475, 0.50, 0.525,0.550, 0.575, 0.60, 0.625, 0.650, 0.675, 0.70, 0.725, 0.750, 0.775,0.80, 0.825, 0.850, 0.875, 0.90, 0.925, 0.950, or 1.00%; Cu may be 0.00,0.025, 0.050, 0.075, 0.10, 0.125, 0.150, 0.175, 0.20, 0.225, 0.250,0.275, 0.30, 0.325, 0.350, 0.375, 0.40, 0.425, 0.450, 0.475, 0.50,0.525, 0.550, 0.575, 0.60, 0.625, 0.650, 0.675, 0.70, 0.725, 0.750,0.775, 0.80, 0.825, 0.850, 0.875, 0.90, 0.925, 0.950, 1.0, 1.25, 1.5,1.75, 2.0, 2.25, 2.50, 2.75, 3.0, 3.25, 3.5, 3.75, 4.0, 4.25, 4.50,4.75, 5.0, 5.25, 5.5, 5.75, 6.0, 6.25, 6.50, 6.75, 7.0, 7.25, 7.5, 7.75,or 8.0%; Nb+Ta may be 0.00, 0.025, 0.050, 0.075, 0.10, 0.125, 0.150,0.175, 0.20, 0.225, 0.250, 0.275, 0.30, 0.325, 0.350, 0.375, 0.40,0.425, 0.450, 0.475, 0.50, 0.525, 0.550, 0.575, 0.60, 0.625, 0.650,0.675, 0.70, 0.725, 0.750, 0.775, or 0.80%; Mn may be 0.00, 0.025,0.050, 0.075, 0.10, 0.125, 0.150, 0.175, 0.20, 0.225, 0.250, 0.275,0.30, 0.325, 0.350, 0.375, 0.40, 0.425, 0.450, 0.475, 0.50, 0.525,0.550, 0.575, 0.60, 0.625, 0.650, 0.675, 0.70, 0.725, 0.750, 0.775,0.80, 0.825, 0.850, 0.875, 0.90, 0.925, 0.950, 1.0, 1.25, 1.5, 1.75,2.0, 2.25, 2.50, 2.75, 3.0, 3.25, 3.5, 3.75, 4.0, 4.25, 4.50, 4.75, 5.0,5.25, 5.5, 5.75, or 6.0%; Si may be 0.00, 0.025, 0.050, 0.075, 0.10,0.125, 0.150, 0.175, 0.20, 0.225, 0.250, 0.275, 0.30, 0.325, 0.350,0.375, 0.40, 0.425, 0.450, 0.475, 0.50, 0.525, 0.550, 0.575, 0.60,0.625, 0.650, 0.675, 0.70, 0.725, 0.750, 0.775, 0.80, 0.825, 0.850,0.875, 0.90, 0.925, 0.950, 1.0, 1.25, 1.5, 1.75, 2.0, 2.25, 2.50, 2.75,3.0, 3.25, 3.5, 3.75, or 4.0%; and the balance Fe. For example, oneembodiment of the powdered metal may include any amount in the range of2-16% Ni; 10-20% Cr; 0-5% Mo; 0-0.6% C; 0-6.0% Cu; 0-0.5% Nb+Ta; 0-4.0%Mn; 0-2.0% Si and the balance Fe. One embodiment of the powdered metalmay include any amount in the range of 2-6% Ni; 13.5-19.5% Cr; 0-0.10%C; 1-7.0% Cu; 0.05-0.65% Nb+Ta; 0-3.0% Mn; 0-3.0% Si and the balance Fe.One embodiment of the powdered metal may include any amount in the rangeof 3-5% Ni; 15.5-17.5% Cr; 0-0.07% C; 3-5.0% Cu; 0.15-0.45% Nb+Ta;0-1.0% Mn; 0-1.0% Si and the balance Fe. One embodiment of the powderedmetal may include any amount in the range of 10-14% Ni; 16-18% Cr; 2-3%Mo; 0-0.03% C; 0-2% Mn; 0-1% Si and the balance Fe. One embodiment ofthe powdered metal may include any amount in the range of 12-14% Cr;0.15-0.4% C; 0-1% Mn; 0-1% Si and the balance Fe. One embodiment of thepowdered metal may include any amount in the range of 16-18% Cr; 0-0.05%C; 0-1% Mn; 0-1% Si and the balance Fe.

The projectiles of the present invention may be made by metal injectionmolded using alloys include high strength steels, stainless steels plusNi and Co super alloys; refractory metals, titanium and copper alloys;and low melting point alloys like brass, bronze, zinc and aluminum. Theprojectiles of the present invention may also be made by metal injectionmolded using stainless Steel: 304L, 316L, 17-4 PH, 15-5 PH, 420, 430,440; Super alloys: Inconel, Hastelloy, Co-based Low Alloy Steels, 2-8%Ni (4600, 4650); Magnetic Alloys: 2-6% Si—Fe, 50% Ni—Fe, 50% Co—Fe;Alloys: Fe-36Ni (Invar), F-15 (Kovar); Materials: Pure Copper,Beryllium-Copper, Brass Steels: AISI M2, M3/2, M4, T15, M42, D2; HeavyAlloys: Tungsten-Copper, W—Fe—Ni, Molybdenum-Copper.

The present invention can be used to metal injection mold variousmaterials including Brass compositions include MPIF CZ-1000-10 having atensile strength of 20,000 PSI, a yield strength of 11,000 PSI, anelongation of 10.5% per inch, and an apparent hardness HRH 70-75; andMPIF CZ-2000-12 having a tensile strength of 30,000 PSI, a yieldstrength of 13,500 PSI, an elongation of 16% per inch, and an apparentHardness HRH 75-80.

The present invention can be used to metal injection mold variousmaterials including Copper compositions include MPIF C-0000-5 having atensile strength of Tensile Strength 23,000 PSI, an elongation of 20%per inch, and an apparent hardness HRH 20-25.

The present invention can be used to metal injection mold variousmaterials including lead. In addition compositions of lead with tinand/or antimony can be formed using the present invention. The presentinvention can be used to form a cup made of harder metal, such ascopper, placed at the base of the bullet (i.e., a gas check) to decreaselead deposits by protecting the rear of the bullet against melting whenfired at higher pressures.

The present invention can be used to metal injection mold variousmaterials including jacketed bullets intended for even higher-velocityapplications generally have a lead core that is jacketed or plated withgilding metal, cupronickel, copper alloys, or steel; a thin layer ofharder metal protects the softer lead core when the bullet is passingthrough the barrel and during flight, which allows delivering the bulletintact to the target. There, the heavy lead core delivers its kineticenergy to the target. In addition to lead cores other more dense metalsincluding hardened steel, tungsten, or tungsten carbide, and even a coreof depleted uranium.

The present invention can be used to metal injection mold variousmaterials including full metal jacket bullets are completely encased inthe harder metal jacket, except for the base. Some bullet jackets do notextend to the front of the bullet, to aid expansion and increaselethality; these are called soft point or hollow point bullets. Steelbullets are often plated with copper or other metals for corrosionresistance during long periods of storage. Synthetic jacket materialssuch as nylon and TEFLON® can also be used as can hollow point bulletswith plastic aerodynamic tips that improve accuracy and enhanceexpansion.

The present invention can be used to metal injection mold variousmaterials including hard cast bullets which includes a hard lead alloyto reduce fouling of rifling grooves.

The present invention can be used to metal injection mold variousmaterials including practice bullets made from lightweight materialsincluding rubber, wax, plastic, or lightweight metal.

The present invention can be used to metal injection mold incendiaryrounds from various materials including an explosive or flammablemixture in the tip that is designed to ignite on contact with a target.The intent is to ignite fuel or munitions in the target area, therebyadding to the destructive power of the bullet itself.

The present invention can be used to metal injection mold explodingrounds from various materials. Similar to the incendiary bullet, thistype of projectile is designed to explode upon hitting a hard surface,preferably the bone of the intended target. Not to be mistaken forcannon shells or grenades with fuse devices, these bullets have only acavity filled with a small amount of low explosive depending on thevelocity and deformation upon impact to detonate.

The present invention can be used to metal injection mold tracer roundsfrom various materials. The tracer rounds have a hollow back, filledwith a flare material. Usually this is a mixture of magnesium metal, aperchlorate, and strontium salts to yield a bright red color, althoughother materials providing other colors have also sometimes been used.Tracer material burns out after a certain amount of time. This type ofround is also used by all branches of the United States military incombat environments as a signaling device to friendly forces. The flightcharacteristics of tracer rounds differ from normal bullets due to theirlighter weight.

The present invention can be used to metal injection mold armor piercingrounds from various materials. Jacketed designs where the core materialis a very hard, high-density metal such as tungsten, tungsten carbide,depleted uranium, or steel. A pointed tip is often used, but a flat tipon the penetrator portion is generally more effective. The most commonbullet jacket material is a copper, nickel, or steel jacket over a leadcore; however, other core materials may be used including depletedUranium, Tungsten as well as other jacketing materials.

In addition multiple layer projectiles may be formed using the metalinjection molding of the present invention. For example, a steel coremay be covered with a layer of lead that is then covered with a layer ofcopper; a depleted Uranium may be covered with a layer of Tungsten thatis then covered with a layer of copper; a steel core may be covered witha layer of lead that is then covered with a polymer layer; a pelletedcore (e.g., small lead pellets, plastic, or a silicone rubber material)may be covered with a layer of lead, copper or polymer; or othervariations.

The present invention can be used to metal injection mold variousmaterials including nontoxic shot such as steel, bismuth, tungsten, andother exotic bullet alloys prevent release of toxic lead into theenvironment.

The present invention can be used to metal injection mold rounds fromvarious materials including blended-metals such as bullets made usingcores from powdered metals and mixtures of different powered metals.

The present invention can be used to metal injection mold frangiblerounds from various materials. These are designed to disintegrate intotiny particles upon impact to minimize their penetration for reasons ofrange safety, to limit environmental impact, or to limit theshoot-through danger behind the intended target. The bullet may be madefrom an amalgam of metal and a hard frangible plastic binder designed topenetrate a human target and release its component shot pellets withoutexiting the target.

The present invention can be used to metal injection mold variousmaterials including solid or monolithic solid metal rounds includingmono-metal bullets intended for deep penetration with slender shapedvery-low-drag projectiles for long range shooting. Such metals includeoxygen free copper and alloys like copper nickel, tellurium copper andbrass including UNS C36000 Free-Cutting Brass.

The present invention can be used to metal injection mold sabot roundsfrom various materials. The sabot round may include a multiple piecebullet having a smaller bullet surrounded by a larger carrier bullet (orsabot) that passes through the barrel and once leaving the barrel thesabot and the smaller bullet separate with the sabot falling to theground fairly close to the barrel and the light weighted smaller bullettraveling down range at a high velocity without any identifiable riflingcharacteristics.

The description of the preferred embodiments should be taken asillustrating, rather than as limiting, the present invention as definedby the claims. As will be readily appreciated, numerous combinations ofthe features set forth above can be utilized without departing from thepresent invention as set forth in the claims. Such variations are notregarded as a departure from the spirit and scope of the invention, andall such modifications are intended to be included within the scope ofthe following claims.

It will be understood that particular embodiments described herein areshown by way of illustration and not as limitations of the invention.The principal features of this invention can be employed in variousembodiments without departing from the scope of the invention. Thoseskilled in the art will recognize, or be able to ascertain using no morethan routine experimentation, numerous equivalents to the specificprocedures described herein. Such equivalents are considered to bewithin the scope of this invention and are covered by the claims.

All publications and patent applications mentioned in the specificationare indicative of the level of skill of those skilled in the art towhich this invention pertains. All publications and patent applicationsare herein incorporated by reference to the same extent as if eachindividual publication or patent application was specifically andindividually indicated to be incorporated by reference.

The use of the word “a” or “an” when used in conjunction with the term“comprising” in the claims and/or the specification may mean “one,” butit is also consistent with the meaning of “one or more,” “at least one,”and “one or more than one.” The use of the term “or” in the claims isused to mean “and/or” unless explicitly indicated to refer toalternatives only or the alternatives are mutually exclusive, althoughthe disclosure supports a definition that refers to only alternativesand “and/or.” Throughout this application, the term “about” is used toindicate that a value includes the inherent variation of error for thedevice, the method being employed to determine the value, or thevariation that exists among the study subjects.

As used in this specification and claim(s), the words “comprising” (andany form of comprising, such as “comprise” and “comprises”), “having”(and any form of having, such as “have” and “has”), “including” (and anyform of including, such as “includes” and “include”) or “containing”(and any form of containing, such as “contains” and “contain”) areinclusive or open-ended and do not exclude additional, unrecitedelements or method steps.

The term “or combinations thereof” as used herein refers to allpermutations and combinations of the listed items preceding the term.For example, “A, B, C, or combinations thereof” is intended to includeat least one of: A, B, C, AB, AC, BC, or ABC, and if order is importantin a particular context, also BA, CA, CB, CBA, BCA, ACB, BAC, or CAB.Continuing with this example, expressly included are combinations thatcontain repeats of one or more item or term, such as BB, AAA, AB, BBC,AAABCCCC, CBBAAA, CABABB, and so forth. The skilled artisan willunderstand that typically there is no limit on the number of items orterms in any combination, unless otherwise apparent from the context.

All of the compositions and/or methods disclosed and claimed herein canbe made and executed without undue experimentation in light of thepresent disclosure. While the compositions and methods of this inventionhave been described in terms of preferred embodiments, it will beapparent to those of skill in the art that variations may be applied tothe compositions and/or methods and in the steps or in the sequence ofsteps of the method described herein without departing from the concept,spirit and scope of the invention. All such similar substitutes andmodifications apparent to those skilled in the art are deemed to bewithin the spirit, scope and concept of the invention as defined by theappended claims.

What is claimed is:
 1. A method of making a metal injection moldedammunition cartridge comprising the steps of: providing an ammunitioncartridge mold; injecting a metal composition into the ammunitioncartridge mold to form a metal injection molded ammunition cartridgecomprising a bottom surface, an extraction flange positioned around thebottom surface; a side wall extending from the extraction flange towarda nose end to form a nose end aperture; a propellant chamber extendingfrom the nose end aperture to the bottom surface; a primer recessextending partially through the bottom surface; a flash hole extendingfrom the primer recess to the propellant chamber to allow passagebetween the propellant chamber and the primer recess; wherein the metalcomposition comprises stainless steel, ceramic alloys,copper/cobalt/nickel/custom alloys, tungsten, tungsten carbide,carballoy, ferro-tungsten, titanium, copper, cobalt, nickel, aluminaoxide, zirconia and aluminum; and removing the metal injection moldedammunition cartridge from the ammunition cartridge mold.
 2. The methodof claim 1, further comprising the step of forming a shoulder in themetal injection molded ammunition cartridge.
 3. The method of claim 2,further comprising the step of forming a neck between the shoulder andthe nose end aperture to form a projectile aperture.
 4. The method ofclaim 1, wherein the metal injection molded ammunition cartridge is a5.56 mm, 7.62 mm, 308, 338, 3030, 3006, 50 caliber, 45 caliber, 380caliber, 38 caliber, 9 mm, 10 mm, 12.7 mm, 14.5 mm, or 14.7 mmammunition cartridge.
 5. The method of claim 1, wherein the metalinjection molded ammunition cartridge is 20 mm, 25 mm, 30 mm, 40 mm, 57mm, 60 mm, 75 mm, 76 mm, 81 mm, 90 mm, 100 mm, 105 mm, 106 mm, 115 mm,120 mm, 122 mm, 125 mm, 130 mm, 152 mm, 155 mm, 165 mm, 175 mm, 203 mm,460 mm, 8 inch, or 4.2 inch.
 6. The method of claim 1, wherein the metalcomposition comprises 102, 174, 201, 202, 300, 302, 303, 304, 308, 309,316, 316L, 316Ti, 321, 405, 408, 409, 410, 415, 416, 416R, 420, 430,439, 440, 446 or 601-665 grade stainless steel.
 7. The method of claim1, wherein the metal composition comprises (a) 2-16% Ni; 10-20% Cr; 0-5%Mo; 0-0.6% C; 0-6.0% Cu; 0-0.5% Nb+Ta; 0-4.0% Mn; 0-2.0% Si and thebalance Fe; (b) 2-6% Ni; 13.5-19.5% Cr; 0-0.10% C; 1-7.0% Cu; 0.05-0.65%Nb+Ta; 0-3.0% Mn; 0-3.0% Si and the balance Fe; (c) 3-5% Ni; 15.5-17.5%Cr; 0-0.07% C; 3-5.0% Cu; 0.15-0.45% Nb+Ta; 0-1.0% Mn; 0-1.0% Si and thebalance Fe; or (d) 10-14% Ni; 16-18% Cr; 2-3% Mo; 0-0.03% C; 0-2% Mn;0-1% Si and the balance Fe.
 8. A method of making a metal injectionmolded ammunition cartridge comprises the steps of: providing anammunition cartridge mold; injecting a metal composition into theammunition cartridge mold to form a metal injection molded ammunitioncartridge comprising a bottom surface, an extraction flange positionedaround the bottom surface; a side wall extending from the extractionflange toward a nose end to form a nose end aperture; a propellantchamber extending from the nose end aperture to the bottom surface; aprimer recess extending partially through the bottom surface; a flashhole extending from the primer recess to the propellant chamber to allowpassage between the propellant chamber and the primer recess; whereinthe metal composition comprises a) 2-16% Ni; 10-20% Cr; 0-5% Mo; 0-0.6%C; 0-6.0% Cu; 0-0.5% Nb+Ta; 0-4.0% Mn; 0-2.0% Si and the balance Fe; b)2-6% Ni; 13.5-19.5% Cr; 0-0.10% C; 1-7.0% Cu; 0.05-0.65% Nb+Ta; 0-3.0%Mn; 0-3.0% Si and the balance Fe; c) 3-5% Ni; 15.5-17.5% Cr; 0-0.07% C;3-5.0% Cu; 0.15-0.45% Nb+Ta; 0-1.0% Mn; 0-1.0% Si and the balance Fe; d)10-14% Ni; 16-18% Cr; 2-3% Mo; 0-0.03% C; 0-2% Mn; 0-1% Si and thebalance Fe; e) 12-14% Cr; 0.15-0.4% C; 0-1% Mn; 0-1% Si and the balanceFe; f) 16-18% Cr; 0-0.05% C; 0-1% Mn; 0-1% Si and the balance Fe; g)3-12% aluminum, 2-8% vanadium, 0.1-0.75% iron, 0.1-0.5% oxygen, and theremainder titanium; or h) about 6% aluminum, about 4% vanadium, about0.25% iron, about 0.2% oxygen, and the remainder titanium; and removingthe metal injection molded ammunition cartridge from the ammunitioncartridge mold.
 9. A method of making a metal injection moldedammunition cartridge comprising the steps of: injecting molding a metalinjection molded ammunition cartridge comprising a bottom surface, anextraction flange positioned around the bottom surface; a side wallextending from the extraction flange toward a nose end to form a noseend aperture; a propellant chamber extending from the nose end apertureto the bottom surface; a primer recess extending partially through thebottom surface; a flash hole extending from the primer recess to thepropellant chamber to allow passage between the propellant chamber andthe primer recess; wherein the metal injection molded ammunitioncartridge comprises 2-16% Ni; 10-20% Cr; 0-5% Mo; 0-0.6% C; 0-6.0% Cu;0-0.5% Nb+Ta; 0-4.0% Mn; 0-2.0% Si and the balance Fe; 2-6% Ni;13.5-19.5% Cr; 0-0.10% C; 1-7.0% Cu; 0.05-0.65% Nb+Ta; 0-3.0% Mn; 0-3.0%Si and the balance Fe; 3-5% Ni; 15.5-17.5% Cr; 0-0.07% C; 3-5.0% Cu;0.15-0.45% Nb+Ta; 0-1.0% Mn; 0-1.0% Si and the balance Fe; 10-14% Ni;16-18% Cr; 2-3% Mo; 0-0.03% C; 0-2% Mn; 0-1% Si and the balance Fe;12-14% Cr; 0.15-0.4% C; 0-1% Mn; 0-1% Si and the balance Fe; 16-18% Cr;0-0.05% C; 0-1% Mn; 0-1% Si and the balance Fe; 3-12% aluminum, 2-8%vanadium, 0.1-0.75% iron, 0.1-0.5% oxygen, and the remainder titanium;or 6% aluminum, about 4% vanadium, about 0.25% iron, about 0.2% oxygen,and the remainder titanium.